You won't get a "decent" range as these things are governed by regulations ... 27MHz RF (radio frequency) to communicate to an average 6 foot coverage, not necessarily line of sight, helps prevent “cross talk” where one device can cause another mouse pointer to move.
I can't see my screen at 6 feet.
Consensus on the Internet is Logitech or Microsoft, there are a load of 'others' out there, but be aware also that if you are a dedicated gamer, then you may not like a wireless mouse/keyboard. The 'response/tracking' speed of around 50Hz a wee bit slow compared to a wired USB mouse of around 100Hz.
Oh, and optical is, of course, the in thing these days.